1. Field of the Invention
The present invention relates to an elastic article with at least one surface having densely populated orientated fibers and a process and apparatus for the manufacture of the article. More particularly, the present invention is directed to an electrostatically flocked glove and a process and apparatus for making the flocked glove.
2. Description of the Prior Art
The present method for applying flock to latex or latex/neoprene articles involves coating the article with a thin layer of latex adhesive and pneumatically blowing flock (most commonly chopped cotton) into the latex adhesive layer while the adhesive is still wet. The flocked latex article is then heated until the latex is dried and cured. The curing results in the cross-linking of the latex polymer molecules by sulfur bonds, or other cross-linking agents/mechanisms which provide memory to the polymer structure, so when stretched it will rebound to its original cured shape. The cured latex adhesive layer is imbedded with the flock. In the case of gloves, the glove is inverted, thus flipping the flocked layer to the inside of the glove. Loose, excess flock can then be removed from the article by washing and drying in a tumbler, chlorinating and drying in a tumbler, or just tumbling, depending on the process. The flocked surface provides a slip layer for donning or removing the glove and absorbing hand moisture.
One major drawback with the present method is that it does not allow the flock to be oriented, since the cotton flock is prepared by chopping and crushing scrap cotton fabric, resulting in random cut lengths of various shapes and sizes. The chopped cotton is pneumatically applied, so the flock adheres to the latex adhesive in whatever random orientation it first contacts the adhesive surface. Thus, the cotton fiber may provide a slip coating for donning and some moisture absorption but it does not provide a smooth, silky, slippery, finished feel, as desired by a glove user.
Electrostatic application of flock to a non-uniform surface, such as a rubber glove surface, can be problematic due to the convoluted surface. When the article is a glove, the glove is typically rotated in an electrical field in order to present all surfaces to the electrostatic applicator. A typical rubber glove manufacturing operation is a continuous conveyer system or conveyer batch system where individual glove rotation may not possible. Therefore the flocking operation must be designed to be a continuous system and designed to keep up with manufacturing speeds. Moreover, the electrostatic flock that has been spent through the charging nozzle or plate needs to be collected and returned through the flock system for another opportunity at adhesion to the adhesive layer on subsequent articles that are being continuously conveyed through the flocking system.
Presently, a known process used to apply an electrostatic flock layer to a polyvinyl chloride polymer (PVC) glove includes the use of non-elastic waterproof adhesives. Since a vinyl glove does not stretch in the typical fashion of rubber articles, the complexity of a waterproof adhesive associated with rubber articles is not experienced, as non-elastic waterproof adhesives are readily available. High temperature cure adhesives are easily applied to the PVC glove since the PVC requires temperatures exceeding 300° F. Thus, the glove and adhesive temperature is matched. However, this technology cannot be equally applied to rubber or rubber-based articles, such as gloves. High temperature cure adhesives are incompatible with rubber-based gloves, since rubber will typically begin to degrade at temperatures of 300° F. and above.
Therefore, there is a need in the art for an efficient process for forming a flocked rubber-based article, such as a glove. The present invention provides for an efficient process that results in an electrostatically flocked rubber-based glove with a smooth, silky feel, which is also very soft, elastic and comfortably flexible. The present invention is achieved in part through the electrostatic application of precision cut, perpendicularly oriented fibers to a glove surface having an elastic adhesive system. Perpendicular orientation and close packing of the electrostatic fibers also allows for much greater moisture absorption to keep hands drier.